A Missouri expert is warning motorists they may encounter a slew of box turtles on roadways in the coming weeks.

Missouri’s state herpetologist, Jeff Briggler, says he’s concerned that the box turtles’ peak seasonal movement begins soon and could collide with the upcoming Memorial Day weekend, the unofficial start of the summer vacation season.

Box turtles sometimes cross roads and busy highways during their travels and are no match for oncoming vehicles.

Briggler says the next two weeks or so will be the turtles’ peak travel period. He hopes drivers will slow down when they spot a turtle crossing a highway or go around it, but he acknowledges that is not always possible on busier thoroughfares.